BoilerFaultCodesWhat the manual says
Manufacturer manualThe water pressure in the heating system is at the lower limit.
From this model's manual
Verified against the Vaillant/Vaillant Vaillantpro 0020308121 05 Ecotecplus Storage Combi Installation installation & service manual.
DIY fix possible
Locate the filling loop (a silver flexi-hose) underneath your boiler or near your pipework.Open the small valve(s) on the loop to allow mains water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valve(s) firmly once the correct pressure is reached to stop the flow.
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Related fault codes
All 125 fault codes on the ecoTEC plus 940 VUI 30/40CS/1-5
Seeing a different code? Every code this model can display, in one place.
194F.000F.001F.002F.003F.010F.011F.012F.013F.020F.022F.023F.024F.025F.027F.028F.029F.032F.035F.040F.042F.044F.047F.049F.057F.061F.062F.063F.064F.065F.067F.068F.070F.071F.072F.074F.075F.076F.077F.078F.080F.081F.083F.084F.085F.087F.088F.089F.090F.092F.095F.096F.097F.105F.194F.195F.196F.317F.318F.320F.321F.322F.323F.324F.325F.326F.327F.330F.334F.336F.337F.338F.342F.343F.344F.347F.363F.707F.905I.003I.144L.016L.022L.025L.032L.095L.096L.097L.105L.144L.194L.195L.196L.319L.320L.322L.343N.013N.027N.032N.089N.095N.096N.097N.100N.144N.194N.270N.317N.319N.324N.343P.000P.001P.003P.008P.021T.001T.002T.003T.004T.005T.006T.007